Met"tle*some*ly

from The Collaborative International Dictionary of English v.0.48

Mettlesome \Met"tle*some\, a.
   Full of spirit; possessing constitutional ardor; fiery; as, a
   mettlesome horse.
   [1913 Webster] -- {Met"tle*some*ly}, adv. --
   {Met"tle*some*ness}, n.
   [1913 Webster]